G Tewani Solutions for Chapter: Statistics, Exercise 2: Archives

If the mean deviation of number $1, 1+d, 1+2d, \dots , 1+100d$ from their mean is $255$, then $d$ is equal to

In a binomial distribution $B\left(n, p=\frac{1}{4}\right).$ If the probability of at least one success is greater than or equal to $\frac{9}{10},$ then $n$ is greater than

If the mean deviations about the median of the numbers $a, 2a, \dots , 50a$ is $50$, then $\left|a\right|$ equals

All the students of a class performed poorly in Mathematics. The teacher decided to give grace marks of $10$ to each of the students. Which of the following statistical measures will not change even after the grace marks were given?

The variance of first $50$ even natural numbers is

The mean of the data set comprising of 16 observations is $16 .$ If one of the observations valued $16$ is deleted and three new observations valued $3,4$and $5$ added to the data, then the mean of the resultant data is

If the standard deviation of the numbers $2,3,a$ and $11$ is $3.5,$ then which of the following is true?

If $\sum _{i=1}^9\left(x_i-5\right)=9$ and $\sum _{i=1}^9{\left(x_i-5\right)}^2=45$, then the standard deviation of the items $x_1,x_2,....,x_9$ is